Performance

Problem:
You are experiencing severe and intermittent backend performance issues on a WordPress + WooCommerce site using WPML. Symptoms include long pending loads with high TTFB when generating HTML pages, and PHP warnings related to gzuncompress() in WPML String Translation.
Solution:
We recommend the following steps to isolate and potentially resolve the issue:
1. Create a full site backup.
2. Update any outdated plugins or themes.
3. Flush any existing cache memory.
4. Deactivate all plugins, including WPML ones.
5. Activate WordPress debug mode. You can find guidance on this at https://developer.wordpress.org/advanced-administration/debug/debug-wordpress/
6. Switch to a default WordPress theme, such as Twenty Twenty.
7. Reactivate the WPML plugins, WooCommerce, and WCML.
8. If the issue resolves, reactivate your theme and other plugins one by one to identify the problematic plugin.
9. Check for error messages in the debug.log file within the wp-content folder.

If these steps do not resolve the issue or if the solution provided here becomes outdated, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If the problem persists, please open a new support ticket for further assistance.